I have recommended this website (https://www.stolaf.edu/depts/chemistry/courses/toolkits/247/...) to many of my students to help them practice naming alkyl substituted alkanes.
The web-page has an "analyze" button that does a great job showing students how to find the longest carbon chain, which is then used to help determine the molecule's IUPAC name.
I've always wondered who was behind the site that I had recommended, but I was never curious enough to poke around and answer my own question.
When I saw "hack-a-mol" and stolaf.edu, I thought, "okay, must be the same person."
People like this (his name is Bob Hanson: https://www.stolaf.edu/people/hansonr/) are hidden gems. He's probably not super-famous, but he's made many great tools and I can only imagine that his students have benefited tremendously from his passion and skills.
press ENTER, the 2D and 3D structures will update.
How do you represent a chemical structure mathematically? Is it a graph? Or something else? It seems more complicated than just a simple graph structure.
Is it a graph? Mostly yes - just ignore anything that's not covalent. It depends a bit on how complicated an interaction you're willing to allow an edge to represent, and how much of reality you're willing to ignore. A few examples of complications are linked below. The depictions may seem trivial, but for large molecules things quickly become ridiculous.
The CACTVS software used on that website is related to Gasteiger at Erlangen.
On top of that all comments on it seem to have shifted by like 10 hours as well (busyant's comment is actually half a day old by now, not 40 minutes).
You can see the timestamps don't match up here: https://news.ycombinator.com/submitted?id=breck (says 11 hours ago).
Or here: https://news.ycombinator.com/threads?id=busyant (says 10 hours ago on his comment on this submission).
This is a process HN has devised to give selected submissions another chance at the front page. See:
The spectrum begins at me being slightly annoyed because I can't tell posts that were posted just now from posts that were posted hours ago.
It probably ends at people arguing in court over such things as prior art in patent cases, or someone trying to submit an online comment as evidence. Imagine Facebook mucking with timestamps... Often when is pretty important.
There's a lot of things in between there which I'll leave to your imagination.
In any case, changing meta information silently can be as bad as silently changing the content of posts themselves and will hurt your credibility as a platform. The reddit CEO did it as a joke once, and that already caused a massive shitstorm.